Answer:
The correct option is C.
Explanation:
According to the transitive property congruence, if first and second triangle are congruent, second and third triangle congruent then first and third triangle must be congruent.
Let A ,B and C are triangles. If

then,

In option on two triangle are congruent. For transitive property we need three triangles therefore option A and B are incorrect.
In option C,


Then,

Therefore option C is correct.
In option D the relation between three triangles is not given therefore option D is incorrect.